Objectives: Licensure of acellular pertussis vaccines awaits the evaluation of several recently completed and ongoing efficacy trials. Results of these trials are dependent upon the laboratory procedures employed to diagnose Bordetella pertussis infection. Similarly, long-term surveillance of the pertussis immunization program requires the development and implementation of sensitive and specific diagnostic procedures. Licensure of less reactogenic acellular pertussis vaccines will provide an opportunity to immunize older age groups, however, data on pertussis morbidity in adults and the role of adults and adolescents in transmission are needed to make appropriate decisions on expanded use of these vaccines. To increase knowledge of pertussis diagnosis and epidemiology, the Laboratory has initiated projects: a) To develop and improve laboratory procedures to diagnose infection with Bordetella pertussis. b) To determine which diagnostic procedures have the highest sensitivity and specificity for pertussis diagnosis at the different stages of illness. c) To apply these techniques to understand epidemiology of pertussis. FY96 Activities: 1. Completed serological assays, continued analysis, and initiated manuscript preparation for a collaborative study with US Navy to determine the prevalence of B. pertussis infection in Marine trainees. Infection was evaluated by culture, serology and by polymerase chain reaction (PCR) technology. From October 1993 through July 1994 samples were collected on recruits reporting to sick call with 7 or more days of cough. Sample collection and culture was performed by the Navy medical staff on 156 subjects. The Laboratory of Pertussis performed about 3200 ELISA tests (approximately 300 of these in FY96) on serum samples and PCR evaluation on nasopharyngeal samples following final optimization and validation of the PCR procedure. 2. Two members assisted in writing an RFP and served on the technical evaluation panel for CDC contract solicitation entitled "Measurement of antibodies to three antigens of Bordetella pertussis". The goal of the study was to develop serodiagnostic assays that could be transferred to state and regional clinical laboratories.